A recap of Tuesday's snowfall amounts
The official snow total at the Chattanooga airport read 0.30".
The official snow total at the Chattanooga airport read 0.30". Skywatchers in Coalmont reported 2", while Tracy City and Monteagle picked up 1", Murphy, 0.60", and Spring City 0.40".
One reason it's so tricky to forecast, is the snow-to-liquid ratio. If snow is melted down to water, the 0.30" we picked up, comes to .02" of water.
Wet snow occurs with a low snow to liquid ratio-this ends up being great for snow making, but causes a headache with slushy roads. The average SLR is 10 inches of snow to 1 inch of water, and a high SLR, like what the Tennessee Valley saw Tuesday January 16th, was a 15 to 1 liquid ratio.
The type of snow that develops in the Tennessee Valley, depends on where the systems derive from. Yesterday's system was called a clipper. Clippers track from Canada.They are fast movers, lack moisture and tend to produce ice crystals that have pockets of dry air in them, thus making the snow dendritic, or white and fluffy. A high SLR is great for roads, but poor for those wanting to make snowmen!
On days like December 8, a low developed over the southwest part of the US and brought enough moisture from the gulf to bring a lower snow to liquid ratio.
On this day, Chattanooga picked up 0.50" of snow. Melt this down, it becomes .04" of water, making it a 12.5 snow to liquid ratio.
Had their been moisture available from the gulf with this past system, the liquid ratio would have been lower, resulting in more slushy roads!
Have a weather story idea? Feel free to email Meteorologist Brittany Beggs.